Your finisher if you don't believe you will kill the target while they are running away. Great tank killer. Overpowered. It does a lot of base damage plus damage based off how much health they are currently missing.

Introduction

In this guide you will learn how to demolish your enemies early game, and carry your team to victory.

This is my first guide, please don't rate it on the flashy features others have. I will try and update the guide to look cleaner ASAP. You can find me in-game under "Putricide" if you'd like to see the guide in action.

Masteries + Runes

Pretty offensive build. With the magic resist and dodge from the defensive tree. You start with low magic resist, so it's nice having 3/3 in Resistance to start with.

For Runes.
Red = Armor Pen.
Yellow = Crit Damage.
Blue = Crit Damage.

You should end with 29 Armor Pen and 12% more Critical Damage. The Armor Pen rips people to shreds early game.

Items

Start with a Long Sword and a Health Potion
Don't go back till you can afford Boots of Swiftness, I personally don't go back till I can afford the boots of swiftness and The Brutalizer
Keep on farming and slaying champions in your lane till you can afford Youmuu's Ghostblade
At this point, you should already have atleast 2-4 kills, and be a very strong ganker. Help other lanes, or keep getting fed in your lane if they are doing well. Work your way to getting Infinity Edge. You are now a monster. Which parts of Infinity Edge you get first is up to your judgement. If I'm getting fed, I just grab the first thing I can afford. If you are not getting to fed, I'd suggest the Pickaxe for more damage.
It should be near end game now, definitely no more laning phase unless you have the biggest stalemate in the world. You should be now working on Phantom Dancer for it's movement speed and critical chance mainly.

1 of the teams should be already trying to push to the nexus at this point, so I would just start doubling up on elixirs. [item=Elixir of Agility] Elixir of Fortitude

If you feel the game is not going to end anytime soon, you may want to build defensive items, late game Garen can be squashed if hes focused. A Guardian Angel might be the best gamble. If you feel you are not dying, just go for another Phantom Dancer. At this time, you should be able to Judgement into a team fight, and bring them down to nothing with the help of your team keeping you alive. (Assuming they are not tanks.)

In the end, it should look something similar to this:
[builder=Garen/f4e9b12ec472478a5187bad1a2121031]

Skilling Order

A lot of people question why I level courage last, it's simply because you should not be going off like super-man at the start. Your ownage relies on having a good laning partner. You should be going in to dominate the laning phase.

Summoner Abilities

Exhaust and Ignite

Working in the team

It's very nice to have a Shen or Rammus laning with you. Their taunts are very powerful when it comes to feeding Garen. When they are stunned or taunted, just eat them alive with Decisive Strike and Judgement. If it's level 1 ganking, use Exhaust and Ignite if you know they do not have cleanse and ghost. Never try first blood on someone with ghost and cleanse. It will not happen. Nearly all champions will die if a shen or rammus attempt first blood like this with you.

Summary

Do not play safe when you have Shen laning with you. Hide in the bush, charge out with Decisive as Shen runs in to taunt. Do not wait for him to taunt, run out together. You want to benefit from the full duration of the taunt. Your decisive strike will make sure you get to the champion in time.